Charles Duguid OBE (6 April 1884 – 5 December 1986) was a Scottish-born medical practitioner, social reformer, Presbyterian lay leader and Aboriginal rights campaigner who lived in Adelaide, South Australia for most of his adult life, and recorded his experience working among the Aboriginal Australians in a number of books. He founded the Ernabella mission station in the far north of South Australia. The Pitjantjatjara people gave him the honorific Tjilpi, meaning "respected old man". He and his wife Phyllis Duguid, also an Aboriginal rights campaigner as well as women's rights activist, led much of the work on improving the lives of Aboriginal people in South Australia in the mid-twentieth century.